<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<script>
function foo(age, name){
    this.age = age;
    this.name = name;
}
//foo(20)
var obj = {};
// 函数借调, 借用  call
foo.call(obj, 20, "李四")   // foo(20, "李四")
console.log(obj);
</script>
</body>
</html>